Arman Shah - Academia.edu (original) (raw)
Papers by Arman Shah
Encyclopedia of Smart Materials, 2018
Surface modification techniques have been proven to enhance resistance towards corrosion, to slow... more Surface modification techniques have been proven to enhance resistance towards corrosion, to slow the process of wearing, to reduce metal ions release, as well as the process of biomaterial osseointegration. Not only that, these techniques could extend the longevity in materials related to implant, primarily because of its response towards the host of body. Generally, these techniques can be further broken down into physical, mechanical, and chemical approaches. As such, this paper presents further information pertaining to the numerous types of methods for modifying surfaces, along with their benefits and drawbacks. Additionally, several other significant aspects are detailed as well in this paper, for example, the materials and biomaterials used for implant, as well as a number of issues concerning the usage of alloy, biomaterial and titanium.
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2020
Magnesium alloys have been widely used in biodegradable applications due to it tends to corrode i... more Magnesium alloys have been widely used in biodegradable applications due to it tends to corrode inside the human body and combined with its initial mechanical property. Current research revealed that the structural stability of the implant is disturbed and lost rapidly due to the increased rate of degradation of magnesium inside the human body. Because of that, non-traditional machining method such as electrical discharge machining (EDM) die sinking process is implemented to create an intricate form with a high tolerance of magnesium alloy. The advantages of EDM are that it allows a versatile adaption of implant behaviour in machining complex 3D structures along with high corrosion resistant properties of electrochemical surface treatment. Various material types with different parameters are investigated to determine the influence of input process parameters on the energy saving, and machining characteristics included surface roughness, material removal rate, and tool wear rate. In addition to improving the machining performance especially in energy-saving, input on the machining parameter needs to be considered due to interaction with added conductive particles which would affect the size of discharge energy. The objective of this paper is to summarize the findings in research of EDM's energy-saving and machining characteristics on magnesium alloy and to explore challenging issues that need to be resolved for future references and recommendations.
Materials Science Forum, 2018
Surface modification of metallic implants is often required to facilitate positive interaction be... more Surface modification of metallic implants is often required to facilitate positive interaction between the implant and the surrounding hard tissue. In the present study, an oxide layer (Cr2O3) was successfully created on a Co-Cr-Mo alloys substrate by using thermal oxidation technique in atmospheric condition. The effect of different carbon content (0.03% and 0.24%) of oxidized Co-Cr-Mo alloys was investigated in terms of its corrosion behavior using electrochemical impedance spectroscopy techniques that immersed in simulated body fluid. The corrosion tests were repeated for five times for each of sample condition. The results demonstrated that thermal oxidation and carbon content have correlation in influencing the corrosion performance in Co-Cr-Mo alloys. A high carbon content sample generates a lower corrosion-rate compared to low carbon content sample even though all samples were treated at similar oxidation temperature and time duration. Observation also showed that less diffus...
International Journal of Academic Research in Business and Social Sciences, 2018
This study is aimed at the development of TIG Welding Training Modules based on The Dick and Rais... more This study is aimed at the development of TIG Welding Training Modules based on The Dick and Raiser Model in the Subject (DJJ3032) of Mechanical Workshop Practice 3 in Malaysia Polytechnic. The Dick and Raiser Model has seven steps that must be systematically implemented to produce a robust module and meet the objectives to be achieved. The study was a quantitative approach that used the survey method to obtain an expert opinion through a questionnaire related to the contents of the TIG Welding Training Module. The research sample consists of four experts who are experienced in TIG field in Malaysia Polytechnic. The findings show that this TIG Welding Training Module has a high content of authenticity. Hence, the TIG Welding Training Module is expected to provide exposure and assist polytechnic lecturers towards teaching and learning as well as helping to understand the Malaysian Polytechnic students.
Jurnal Teknologi, 2016
Cathodic arc physical vapor deposition (CAPVD) is one of the promising techniques that have a pot... more Cathodic arc physical vapor deposition (CAPVD) is one of the promising techniques that have a potential to coat titanium nitride (TiN) on biomedical implants due to its good adhesion and high evaporation rate. However, this method emits microdroplets which have the possible detrimental effect on the coating performance. Past studies indicated that micro droplets can be controlled through proper deposition parameters. In the present work, an attempt was made to study the effect of nitrogen gas flow rates (100 to 300 sccm) on TiN coating of the Ti-13Zr-13Nb biomedical alloy. Scanning electron microscopy (SEM) was used to evaluate surface morphology and coating thickness while crystal phase of the coated substrates was determined using X-Ray Diffraction (XRD). Image analysis software was employed to quantify microdroplets counts. Results show that higher nitrogen gas flow rate able to decrease a significant amount of microdroplets and concurrently increase the thickness of TiN coating....
Aging
Previous studies demonstrated that lifelong treatment with a slow H2S releasing donor extends yea... more Previous studies demonstrated that lifelong treatment with a slow H2S releasing donor extends yeast chronological lifespan (CLS), but it is not clear when the action of H2S benefits to CLS during yeast growth. Here, we show that short H2S treatments by using NaHS as a fast H2S releasing donor at 96 hours after inoculation extended yeast CLS while NaHS treatments earlier than 72 hours after inoculation failed to do so. To reveal the mechanism, we analyzed the transcriptome of yeast cells with or without the early and late NaHS treatments. We found that both treatments had similar effects on pathways related to CLS regulation. Follow-up qPCR and ROS analyses suggest that altered expression of some antioxidant genes by the early NaHS treatments were not stable enough to benefit CLS. Moreover, transcriptome data also indicated that some genes were regulated differently by the early and late H2S treatment. Specifically, we found that the expression of YPK2, a human SGK2 homolog and also a key regulator of the yeast cell wall synthesis, was significantly altered by the late NaHS treatment but not altered by the early NaHS treatment. Finally, the key role of YPK2 in CLS regulation by H2S is revealed by CLS data showing that the late NaHS treatment did not enhance the CLS of a ypk2 knockout mutant. This study sheds light on the molecular mechanism of CLS extension induced by H2S, and for the first time addresses the importance of H2S treatment timing for lifespan extension.
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2020
Beryllium oxide slip casting is used to obtain products of complex shapes of various designs. Ult... more Beryllium oxide slip casting is used to obtain products of complex shapes of various designs. Ultrasonic activation improves the rheological properties of the beryllium oxide slip. In experiments with ultrasonic activation, physicochemical properties of a beryllium oxide slip were obtained. The calculated beryllium oxide casting data was obtained using the Balkley-Herschel model. The phase transition from liquid to viscousplastic state indicates the presence of a crystallization zone consisting of liquid and solid particles of beryllium oxide. Comparison of calculated data with experiment is presented.
Encyclopedia of Smart Materials, 2018
Surface modification techniques have been proven to enhance resistance towards corrosion, to slow... more Surface modification techniques have been proven to enhance resistance towards corrosion, to slow the process of wearing, to reduce metal ions release, as well as the process of biomaterial osseointegration. Not only that, these techniques could extend the longevity in materials related to implant, primarily because of its response towards the host of body. Generally, these techniques can be further broken down into physical, mechanical, and chemical approaches. As such, this paper presents further information pertaining to the numerous types of methods for modifying surfaces, along with their benefits and drawbacks. Additionally, several other significant aspects are detailed as well in this paper, for example, the materials and biomaterials used for implant, as well as a number of issues concerning the usage of alloy, biomaterial and titanium.
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2020
Magnesium alloys have been widely used in biodegradable applications due to it tends to corrode i... more Magnesium alloys have been widely used in biodegradable applications due to it tends to corrode inside the human body and combined with its initial mechanical property. Current research revealed that the structural stability of the implant is disturbed and lost rapidly due to the increased rate of degradation of magnesium inside the human body. Because of that, non-traditional machining method such as electrical discharge machining (EDM) die sinking process is implemented to create an intricate form with a high tolerance of magnesium alloy. The advantages of EDM are that it allows a versatile adaption of implant behaviour in machining complex 3D structures along with high corrosion resistant properties of electrochemical surface treatment. Various material types with different parameters are investigated to determine the influence of input process parameters on the energy saving, and machining characteristics included surface roughness, material removal rate, and tool wear rate. In addition to improving the machining performance especially in energy-saving, input on the machining parameter needs to be considered due to interaction with added conductive particles which would affect the size of discharge energy. The objective of this paper is to summarize the findings in research of EDM's energy-saving and machining characteristics on magnesium alloy and to explore challenging issues that need to be resolved for future references and recommendations.
Materials Science Forum, 2018
Surface modification of metallic implants is often required to facilitate positive interaction be... more Surface modification of metallic implants is often required to facilitate positive interaction between the implant and the surrounding hard tissue. In the present study, an oxide layer (Cr2O3) was successfully created on a Co-Cr-Mo alloys substrate by using thermal oxidation technique in atmospheric condition. The effect of different carbon content (0.03% and 0.24%) of oxidized Co-Cr-Mo alloys was investigated in terms of its corrosion behavior using electrochemical impedance spectroscopy techniques that immersed in simulated body fluid. The corrosion tests were repeated for five times for each of sample condition. The results demonstrated that thermal oxidation and carbon content have correlation in influencing the corrosion performance in Co-Cr-Mo alloys. A high carbon content sample generates a lower corrosion-rate compared to low carbon content sample even though all samples were treated at similar oxidation temperature and time duration. Observation also showed that less diffus...
International Journal of Academic Research in Business and Social Sciences, 2018
This study is aimed at the development of TIG Welding Training Modules based on The Dick and Rais... more This study is aimed at the development of TIG Welding Training Modules based on The Dick and Raiser Model in the Subject (DJJ3032) of Mechanical Workshop Practice 3 in Malaysia Polytechnic. The Dick and Raiser Model has seven steps that must be systematically implemented to produce a robust module and meet the objectives to be achieved. The study was a quantitative approach that used the survey method to obtain an expert opinion through a questionnaire related to the contents of the TIG Welding Training Module. The research sample consists of four experts who are experienced in TIG field in Malaysia Polytechnic. The findings show that this TIG Welding Training Module has a high content of authenticity. Hence, the TIG Welding Training Module is expected to provide exposure and assist polytechnic lecturers towards teaching and learning as well as helping to understand the Malaysian Polytechnic students.
Jurnal Teknologi, 2016
Cathodic arc physical vapor deposition (CAPVD) is one of the promising techniques that have a pot... more Cathodic arc physical vapor deposition (CAPVD) is one of the promising techniques that have a potential to coat titanium nitride (TiN) on biomedical implants due to its good adhesion and high evaporation rate. However, this method emits microdroplets which have the possible detrimental effect on the coating performance. Past studies indicated that micro droplets can be controlled through proper deposition parameters. In the present work, an attempt was made to study the effect of nitrogen gas flow rates (100 to 300 sccm) on TiN coating of the Ti-13Zr-13Nb biomedical alloy. Scanning electron microscopy (SEM) was used to evaluate surface morphology and coating thickness while crystal phase of the coated substrates was determined using X-Ray Diffraction (XRD). Image analysis software was employed to quantify microdroplets counts. Results show that higher nitrogen gas flow rate able to decrease a significant amount of microdroplets and concurrently increase the thickness of TiN coating....
Aging
Previous studies demonstrated that lifelong treatment with a slow H2S releasing donor extends yea... more Previous studies demonstrated that lifelong treatment with a slow H2S releasing donor extends yeast chronological lifespan (CLS), but it is not clear when the action of H2S benefits to CLS during yeast growth. Here, we show that short H2S treatments by using NaHS as a fast H2S releasing donor at 96 hours after inoculation extended yeast CLS while NaHS treatments earlier than 72 hours after inoculation failed to do so. To reveal the mechanism, we analyzed the transcriptome of yeast cells with or without the early and late NaHS treatments. We found that both treatments had similar effects on pathways related to CLS regulation. Follow-up qPCR and ROS analyses suggest that altered expression of some antioxidant genes by the early NaHS treatments were not stable enough to benefit CLS. Moreover, transcriptome data also indicated that some genes were regulated differently by the early and late H2S treatment. Specifically, we found that the expression of YPK2, a human SGK2 homolog and also a key regulator of the yeast cell wall synthesis, was significantly altered by the late NaHS treatment but not altered by the early NaHS treatment. Finally, the key role of YPK2 in CLS regulation by H2S is revealed by CLS data showing that the late NaHS treatment did not enhance the CLS of a ypk2 knockout mutant. This study sheds light on the molecular mechanism of CLS extension induced by H2S, and for the first time addresses the importance of H2S treatment timing for lifespan extension.
Journal of Advanced Research in Fluid Mechanics and Thermal Sciences, 2020
Beryllium oxide slip casting is used to obtain products of complex shapes of various designs. Ult... more Beryllium oxide slip casting is used to obtain products of complex shapes of various designs. Ultrasonic activation improves the rheological properties of the beryllium oxide slip. In experiments with ultrasonic activation, physicochemical properties of a beryllium oxide slip were obtained. The calculated beryllium oxide casting data was obtained using the Balkley-Herschel model. The phase transition from liquid to viscousplastic state indicates the presence of a crystallization zone consisting of liquid and solid particles of beryllium oxide. Comparison of calculated data with experiment is presented.